On my '54 Tiger 100,I had to change out magneto's and even though I have the factory shop manual,the Clymer manual from 1951, and the Hayne's manual, it is still a little vague, and required a bit of thinking to finally believe I knew what they were talking about.
The one thing I have trouble with, is keeping the mag armature from moving and or turning as I slip the automatic advance unit (set in the advanced position using a wedge) on to the magneto shaft.That think turns if you blow on it hard enough!
Anybody got any insight into this, that they can share with me, or put the procedure down in their own words.I think I got it pretty close, as I did get the bike to fire up, and except for the carbs being gummed up, Igot it to run long enough to start responding to the throttle.Sounded good anyway!!!
I would image that you can grab the points cam with a pair of needle nose or similar to hold the mag in place while you slide the drive assembly onto the shaft. You might need a helper if you can't hold the advance unit in the full advance position with one hand. I have always had the good fortune of a well behaved mag (stays where I want it when I time it).
Make sure that you time one side, check the other side and even out the difference. I don't think any of the manuals call for you to do that, but the Lucas mags are usually off a few degrees. You are better off with both cyl firing at the same point than having one at the factory spec and the other not.
Jon - Not to worry... you are now experiencing "true Brit". The timing on all mags slips a bit when setting them up. Set your timing wheel where you know it's dead on, and chock the advance unit.
When the degree wheel is "on" and the buzz box is telling you the armature is "on" you can place a socket large enough to step over the AA center bolt and give the gear a slight tap onto the taper, then tighten the center bolt.
You'll see you're high or low, then you have to adjust your proceedure from there. I've hardly ever seen a mag timed in less than 3 tries.
PS. The old books said to use cigarette paper in the points, but you go ahead an use a modern "buzz box", OK?
Hope this helps.
Don't hide 'em, Ride 'em !!
RF Whatley Cornelia, GA
"Shop Boy" at Rodi British Bikes
Re: Timing a ' 54 Tiger using a Lucas K2F Magneto#78270 03/30/053:09 am03/30/053:09 am
I appreciate the help. Now I've been riding Triumph's for 18 years (since I was 18!!!)and RedNeck, I've never heard of a buzz box ?!!! Now,I have to admit that they were all unit twins, and I've just recently got to the point of having running Pre-Units, so please let me know what this is, and I'll make sure to go get one.Also,the bike only has a magneto and no other electrics right now, since it was set up for flat tracking, I guess ? Anyway, I'll be wiring it for street riding of course.
Brent,one of my manuals does mention that you need to time both sides,it may be the Clymer manual, I'll take a look, and it may be the Haynes believe it or not ?!!! :stout: :stout: :stout:
The 'Buzz Box' that RedNeck is talking about is a resistance tester? My buddy that owns one of the local shops here has one. Basically you use it just like a voltage meter, but when you get a connection it makes a buzzing sound. Neat piece, and is very useful for finding shorted out points, etc. I don't have one, so I use the cigarette wrapper method for timing the mags. Getting harder to come by for me, since I quit smoking almost 10 years ago!
Didn't realize that the aftermarket manuals had that info. I'm pretty sure that Triumph manuals don't have that info, but I could be wrong. I do know that the method for timing the mag in the factory manuals is not the best way (measured drop of the piston) as most of the bikes have domed pistons. Degree wheel is definately the way to go.
Many of the VOM (volt ohm meters) have a feature that will buzz when you have a dead short. If you attach one lead to your point plate and one to the movable contact, set it on the proper position then the meter will "buzz" when the points make contact. The other option is to buy one of those cheap continuity testers (harbor freight or sears) put an alligator clip on the point, attach on lead to the point plate and the other to the movable contact and look for the light when the contact closes.
Re: Timing a ' 54 Tiger using a Lucas K2F Magneto#78274 03/31/0510:46 am03/31/0510:46 am